As human development brings people and wild animals into closer contact, strategies that minimize conflicts between the two will help keep people and their property safe while preserving healthy wild animal populations. Since wild animals are often attracted to food in urban spaces, limiting their access is one way to reduce conflicts such as property damage and vehicle collisions. This study investigated how the large-scale introduction and use of bear-resistant garbage containers influenced black bear behavior in Durango, Colorado, a mountainous city with high rates of human-bear conflict.

Study Context: Durango’s Bears

While Durango passed an ordinance in 2010 requiring residents to secure their garbage, widespread compliance can be challenging to achieve in practice. To test whether the large-scale use of bear-resistant garbage containers would meaningfully reduce human-bear conflict, the city and its partners distributed over 1,000 of them in spring 2013 — one for every home in two designated residential areas. They found less evidence of scattered trash in areas where all homes had the containers compared to adjacent areas operating normally under the ordinance.

The current study builds on this work by examining the movement patterns of individual bears to evaluate how the rollout of the bear-resistant containers influenced their behavior (i.e., where they went and how they moved). It provides additional evidence that the intervention worked — not only in keeping bears out of garbage, but also in deterring them from residential areas, which likely lowered the risk of other, non-garbage-related conflicts.

From Collars To Clues: Decoding Bear Behavior

The authors relied on location data from bears who had been collared and tracked for a separate study. Across six summers (the months of July through September from 2011 to 2016), seven bears had visited areas with bear-resistant containers at least once. These bears provided the primary data used to assess the effect of the intervention.

To track behavior, the authors analyzed where the bears went, how fast they traveled, and how much their paths changed direction. Specifically, they looked at whether the bear-resistant containers deterred bears and/or caused bears to move faster and straighter through areas where each house had one. The authors also measured how this behavior changed over time.

Using statistical models that accounted for bears’ baseline behavior in Durango’s urban landscape, the authors determined what explanation best described how bears responded to the widespread implementation of bear-resistant containers.

What The Data Showed

The analysis revealed some encouraging results:

• Widespread bear-resistant containers worked to change bear behavior. By the fourth summer after the containers were distributed, bears had become 30% less likely to visit areas where every home had one. Meanwhile, they were 10% more likely in summer 2016, compared to 2013, to visit similar areas where people were storing garbage as usual.
• Bear-resistant containers became even more effective over time, possibly because bears learned to avoid them. Three bears were able to provide data both before and at least two summers after the containers were introduced. In the summers following the intervention, these bears increasingly shifted away from visiting areas with many bear-resistant containers and toward areas with typical garbage storage, suggesting they were learning that the containers were not worth the effort.

The effects on speed and straightness were inconclusive. The researchers expected bears to move faster and straighter in areas with many bear-resistant containers, which could have indicated they took less interest in these environments. However, there was no clear evidence that the intervention influenced either measure of movement.

The containers used in this study required residents to manually lock them, meaning that even in areas where all homes received a bear-resistant container, only about 71% used them as intended. The authors suggest that automatically locking containers would help increase overall compliance and effectiveness.

Limitations

This study tracked a small number of black bears in one region, and because the authors relied on location data collected for a different study, they could only look at females three years of age or older. Other bear populations might respond differently to bear-resistant containers. However, the authors note that their findings align with the research mentioned earlier, which looked at bears of all age groups and sexes during the same time period and found that the containers effectively reduced garbage-related conflicts.

The authors also mention that the changes in behavior observed over the course of this study could partly be explained by the particular mix of bears contributing to each summer’s data. However, the three bears with the most comprehensive data did show evidence of learning over time to avoid the areas with widespread bear-resistant containers.

Secure Garbage Makes Safer Communities

This study found that when bear-resistant garbage containers were widely introduced in residential areas, bears began to avoid these areas over time. Residential neighborhoods — especially those with backyards — are naturally attractive to bears, making them particularly helpful to target. The authors suggest that bear-resistant containers are a strategic investment, especially if they lock automatically.

As this study demonstrates, ordinances requiring secure garbage storage play a foundational role, but their success depends on resident compliance. Animal advocates can help by promoting education about secure garbage storage practices, backing policies that increase access to tools like bear-resistant containers, and supporting fair enforcement of ordinances.